Impact of drug-eluting versus bare-metal stents on mortality in patients with anemia.

OBJECTIVES Our aim was to assess the incidence of all-cause mortality in patients with anemia undergoing percutaneous coronary intervention (PCI) receiving drug-eluting stents (DES) or bare-metal stents (BMS). BACKGROUND Anemia has been associated with poor clinical outcomes in patients undergoing PCI. However, it is unknown whether stent selection (DES or BMS) has a differential outcome in this high-risk group. METHODS Anemia was defined as a hematocrit below 36% for female subjects and below 40% for male subjects as defined by the World Health Organization. All patients undergoing PCI with DES or BMS alone from March 2003 to June 2007 were included. The primary end point was all-cause mortality. Anemia was further characterized using mean corpuscular volume as microcytic, normocytic, or macrocytic. RESULTS A total 11,181 patients underwent PCI over a 4.5-year interval; of these, 2,172 met our inclusion criteria. There were a total of 429 deaths. The majority of patients had normocytic anemia (n = 1,931). Of the 3 anemia subtypes, macrocytic anemia (DES 26%, BMS 44%) had the highest mortality followed by normocytic (DES 17%, BMS 25%) and microcytic (DES 13%, BMS 18%) anemia, respectively. All-cause mortality was significantly lower with DES in unadjusted and multivariable adjusted Cox proportional models (adjusted hazard ratio: 0.66, 95% confidence interval: 0.54 to 0.82; p < 0.001). CONCLUSIONS In an adjusted analysis, the use of DES as compared with the use of BMS was associated with decreased mortality in patients with anemia. Additionally, among anemia subtypes, macrocytic anemia had the highest mortality.